Disazo dyestuffs



Patented Oct. 26, 1948 UNITED STATES PATENT OFFICE I 2,452,263 msaz'o 'DYES'TUFFS Rudolf l tueg g, Basel, Switzerland, assignor to Ciba Limited, Basel, Switzerland, a Swiss firm No Drawing.. Application January 20, 1947, Se-

rial No. 723,205. In Switzerland'January 31,

4 Claims.

According to this invention new disazo-dye stufis suitable for dyeing animal fibers are made by coupling a diazo-compound of a monoazodyestufi of the general formula inwhich R1 represents hydrogen or an alkyl or cycloalkyl radical, R2 represents hydrogen or an alkyl, aryl, aralky'l or cycloalkyl radical, R3, represents a, benzene radical, and R4 represents a naphthalene radical in which the N=N-- and NH2 groups are in para-position relatively to each other, with a l-N-alkylaminoor I-N-arylamino naphthalene 8-sulfonic acid, and so choosing the components that the final dyestufi contains two sulfonic acid groups.

Especially valuable results are obtained by using as a starting material a diazo-compound of a monoazo-dyestufi of the general formula N-O2SR;N=NR4NH2 2 in which R1 represents an alkyl radical containing at most four carbon atoms, R2 represents the residue of a benzene sulfonic acid, R3 represents a benzene radical in which the groups /NO2S R2 and --N= l \T-- are in meta-position orpara-posi tion relatively to each other, and R4 represents a naphthalene radical in which the N-- N and NH2 groups are in para-positin relatively to each other, and coupling such a diazo-compound with a 1-N-aryl-aminonaphthalene- 8 '-.sulfoni'c acid, and so choosing the components that 'the final dyestufi contains two sulfonic acid groups.

Accordingly, there are especially valuable as starting materials diazo-compounds of monoazodyestufis of the general formula in'which R1 representsamethyl or ethyl group, and one X represents hydrogen and the other X-hydrogen, halogen or a methyl group, and'as couplingconiponents there are primarily suitable 1 2 l-N-phenyla mlnoor ,l-N-para-tolylaininonaphthalene-8-sulfonic acid.

The monoazo-compounds used as starting ma- 7 terials are obtained in known manner, for example, by coupling a diazotised aminoaryl sulfonamide of the general formula /N02SRs-NH2 R2 in which R1, R2 and R3 have the meanings given above,with an amine of the naphthalene series capable of coupling in the 4-position relatively to the NI-I2 'group. s

Aminoaryl sulfonamides of the above general formula can be made by methods in themselves known, for example, by reacting preferably l-nitrobenzene-3-su1fochloride, or alternatively 1- methyl-2-nitrobenzene-r4 -sulfochloride, l-methoxy-2-nitrobenzene-4-sul fo-chloride, l-methyl -4 nitrobenzene 6-sulfochloride, l-chloro 2 nitrobenzene-l-sulfochloride, 1 chloro-4 nitrobenzene-G-srllfochlorida or 1-nitrobenzene-2 or -4- sulfochloride withammonia or a primary or secondary amine, if desired, sulfonating the resulting nitroaryl sulfonamide, and reducing the nitro group to an amino group. As primary or secondary amines suitable for reaction with nitrobenzene sulfochlorides there may be mentioned, for example: Methylamine, monoethanolamine, dimethylamine, dipropylamine, butylamine, diethanolamine, cyclohexylamine, aminobenzene, l-ain'inoA-methylbenzene, 1-amin0-2rnethoxybenzene, NV-methylaminebenzene, N-ethylaminobenzene, l-N-hydroxyethylaminobenzene, 1--N- ethylaminobenzene-3-sulfonic acid and thelike.

As amines of the naphthalene series capable of coupling in the paraposition withrespect to th NI-Iz groii-pithereicome intoconsider'ation princi pally -1-"aminonaphthalene, l-aminonaphthale'ne- 6 or -'7-sulfonicacid or commercial mixtures of tion are new and correspond to the general formula -0 2SR a-N=N-R 4N=NR 5 in which R1 represents hydrogen or an alkyl or cycloalkyl radical, R2 represents hydrogen or an alkyl, aryl, aralkyl or cycloalkyl radical, Ra represents a benzene radical, R4 represents a napthalene radical in which the two azo-groups are in para-position relatively to each other, and R5 represents the residue of a l-N-alkyl-aminoor l-N- arylamino-naphthalene-8-sulfonic acid connected in the 4-position to the azo-group.

The new dyestuffs obtainable by the invention dye animal fibers fast violet-blue to navy blue tints. As compared with known dyestuffs of similar constitution the new dyestuffs are distinguished by yielding dyeings of better fastness to washing. k I

The following examples illustrate the invention, the parts are by weight:

Example 1 6.8 parts of 3-aminobenzene sulfonic acid-(1) [N-methylanilide-X-sulfonic acidl are dissolved in 50 parts of water with the calculated quantity of sodium hydroxide, and mixed with 1.4 parts of sodium nitrite. I ice parts of concentrated hydrochloric acid are introduced. The resulting white suspension of the diam-compound is coupled in the usual manner with 3 parts of l-amino-naphthalene, and then the red-violet dyestufi is separated by filter.- ing with suction and washed with dilute hydrochloric acid.. It is then suspended in 100 parts of water and dissolved by the addition of sodium hydroxide. The weakly alkaline solution is mixed with 2 parts of sodium nitrite, and diazotized by introducing 10 parts of concentrated hydrochloric acid.' The brown diazo-compound is isolated, washed withdilute hydrochloric acid, and suspended in parts of water, 6 parts of l-phenylaminonaphthalene-8-sulfonic acid are dissolved in 40 parts of water with the calculated quantity of sodium hydroxide. The weakly alkaline solution is rendered weakly acid by the addition of a small quantity of acetic acid, mixed with 4 parts of crystalline sodium acetate, and then mixed with the above diazo-suspension while cooling; From.

After a few hours the couplin is complete. the deep blue solution obtained after neutralization with sodium carbonate the dyestufi is precipitated at 70 C. by the addition of sodium chloride. The dyestuif of the formula dimer lene-8-sulfonic acid, a blue dyestuff is obtained having similar properties. A similar procedure may be followed with any ofthe other starting materials mentioned in the'opening part of this specification.

After the addition of 30 parts of Example 2 35.6 parts of 3-aminobenzene sulfonic acid-(1) (N-ethylanilide-3-sulfonic acid) are suspended in 200 parts of water and dissolves under weakly alkaline conditions with 4 parts of sodium hydroxide. The'solution is mixed with 7 parts of sodium nitrite, and then 30 parts of concentrated hydrochloric acid are introduced at a temperature below 5C. A suspension of the sparingly soluble diazocompound is obtained, which is then coupled in the usual manner with 14.3 parts of l-aminonaphthalene. The blue-red amlnoazo-dyestufi is suspended in 500 parts of water, dissolved under weakly alkaline conditions with sodium hydroxide, and mixed with a concentrated solution of 8 parts of sodium nitrite and with parts of concentrated hydrochloric acid. When the diazotization is finished, the red-brown diazo-compound is isolated, and introduced into a solution of '32 parts of sodium l-phenylaminonaphthalene-8-sulfonate, 20 parts of crystalline sodium acetate and 3 parts of acetic acid in 500 parts of water. After a few hours the dyestuff formation ceases. The dyestufi of the formula hiqHQ after conversion into its disodium salt by means of sodium carbonate, is precipitated at C.

with a saturated solution of sodium chloride, isolated while hot, and washed with a dilute solution of sodium chloride. When dry it is a dark powder, which dissolves in water with a deep blue coloration and dyes wool navy blue from an acetic acid bath.

By using the sodium salt of l-(4'-tolylamino) naphthaIene B-suIfonic acid, instead of the sodium salt of 1-phenylaminonaphthalene-8-sulfoni-c acid, there is obtained a similar dyestufi which dyes Wool.

Example 3 34.2 parts of 4-aminobenzene sulfonic acid-(1) N-methylanilide-X-sulfonic acid) are suspended in 250 parts of water and dissolved with 4 parts of sodium hydroxide. After the addition of 7 parts of sodium nitrite, 30 parts of concentrated hydrochloric acid are introduced at a temperature below 10 C. The yellowish diam-suspension is coupled in the usual manner with 14.3 parts of 1- aminonaphthalene. The blue-red. amino-azudyestuff is suspended in 500 parts of water, then SOaH rendered weakly alkaline with sodium hydroxide,

parts of crystalline sodium acetate and 3 parts of acetic acid in 400 parts of water. When the formation of dyestufi has ceased, the blue dyestufisuspension is mixed at 70 C. with sodium carbonate until it has a weakly alkaline reaction, and then the dyestufi of the formula SOaH is precipitated with a saturated solution of sodium chloride. The dyestuff is isolated, and washed with a dilute solution of sodium chloride and dried. A. dark blue powder is obtained which has a superficial greenish lustre, dissolves in water with a blue coloration and dyes wool blue from a acetic acid bath.

Example 4 37.7 parts of 3-amino-6-chlorobenzene sulfonic acid- (1) (N-methylanilide-X-sulfoni'c acid) are suspended in 250 parts of water and dissolved with 4 parts of sodium hydroxide. The whole is mixed wit-h 7 parts of sodium nitrite, and then with 30 parts of concentrated hydrochloric acid at'aternperature below 5 C. The diam-compound, which with 60 parts of concentrated hydrochloric acid.

rmo s SOaH The brown diam-compound is'isolated after a few' hours, washed withdilute hydrochloric acid, suspended in -l00 parts of water, and introduced into a solution of 32 parts of sodium l-phenylaminonaphthalene-8-sulfonate, parts of crystalline sodium acetate and 5 parts of acetic acid in 400 parts of water. After a few hours the dyestufi suspension is mixed with sodium carbonate until it has a weakly alkaline reaction. At 75 C. the dyestuff is precipitated with a saturated solution of sodium chloride, filtered hot, and washed with a dilute solution of sodium chloride. The dry dyestuff of the formula is a blue powder having a superficial reddish lustre, which dissolves in water with a blue coloration and dyes wool blue from an acetic acid bath.

A similar dyestuff is obtained by using the sodium salt of 1-(4'-tolylamino) -naphthalene-8- sulfonic acid, instead of the sodium salt of lphenyl-aminonaphthalene-8-sulfonic acid, or 3- amino 4 chlorobenzene sulfonic acid-(1) -(N- methylanilide-l -sulfonic acid), instead of 3- amino-G-chlorobenzene sulfonic acid-(1) (N- methylanilide-X-sulfonic acid).

35.6 partsoi 3-amino-4-methylbenzene sulfonic NEG-CH:

SOsH

mixed with 7 parts'offsodium nitrite, an 30 parts ofconcent'rate'd hydrochloric-a" d are introduced at a temperature below 5 C. The

sparingly soluble 'diazocompound soon pr'ecipi;

tates, and is coupled in th'e usual manner with M3 ,parts of=l-aminoriaphth-alene. {Ihe amino-azodyestuffis suspended in 900 parts of water, dis-' solved to a weakly alkaline reaction withsodium hydroxide; and mixed with a concentrated-solution of 8 parts of sodium nitrite and with 6 0 parts of "concentrated hydr'dchloric acid;v The brown diazo-corrip'ou'iid is isolated after aff w h'o'urs, wasi'idwith dilutehydrochloric acid and suspended in 200 parts of water. The resulting magma is mixed with a solution of 32 parts of sodium 1-phenylarninonaphthalene fiasulfonate, 20 parts of crystallined sodium acetate and 4 parts of acetic acidin"4Q0 parts of water. After a 1:ew hours the "coupling 'is finished. "The' iivhole is mixed at 70 C.,with-sodium carbo'nate until itv has a weakly alkaline reaction, and then the dyestuii "(if the formula is precipitated with a saturate solution of Example 6 0.2 part of the dyestuff obtained as described in the first paragraph of Example 1 is dissolved in 400 parts of water, 1 part of crystalline sodium sulfate is added to the dyebath, and 10 parts of wool are entered at id-50 C. 0.3 part of acetic acid are then added, the bath is slowly brought to a gentle boil in the course of /2 hour, and dyeing is carried on at that temperature for hour. After washing and drying the material, a fast deep blue dyeing is obtained.

7 8 What I claim is: r 1. A disazo-dyestui! of the iormula N-o, N= N=N NH -1 BOaH in which R1 represents an alkyl radical containing at most two carbon atoms, one x represents 10 hydrogen and the-other :c a. member selected from the group consisting of hydrogen and methyl, and y-represents a. member selected from the group consisting of hydrogen and methyl.

2.- The disazo-dyestufl' of the formula 15 $0 3; The disazo-dyestufl of the formula 4. The disazo-dyestufl of the formula I CzHi RUDQLF RUEGG.

REFERENCES CITED The following references are-"of record in the file of this patent:

UNITED STATES PATENTS FOREIGN PATENTS Number Name Date Number Country Date 2,084,668 Reindel et a1 Mar. 17, 1936 13,626 Great Britain 1895 2,222,749 Krebser Nov. 26, 1940 408,590 7 Great Britain Mar. 29, 1934 2,257,694 Krebser Sept. 30, 1941 546,595 Great Britain July 21, 1942 2,399,064 Schetty Apr. 23, 1946 

